“Happily Ever After.”

I have always found the “Lost” episodes pegged to Desmond to be some of the most engaging the show has produced through the years, and last night’s “Happily Ever After” proved to be no exception. Best hour of the season. By far.

From the opening scenes in which Widmore horrifies Desmond by informing him, “I’ve brought you back to the island” (for a wicked experiment, no less), through the tense flash-sideways sequences involving Charlie, Eloise and Daniel, and all the way up to Desmond meeting Penny (Be still, my heart) on the stadium steps, this episode had me in its grips — my heart pounding and my jaw dropping the entire way.

Epic.

What I think fueled the excitement — besides all the fun callbacks, juicy twists, surprising reveals and a remarkable performance by Henry Ian Cusick — was the sense of forward progress. More than ever, we were given glimpses into how the sideways world and the island storyline play off one another. It felt like we were going somewhere (a feeling that hasn’t always existed this season). That we were making strides toward an end game that could be enthralling and mind-blowing. In other words, it renewed our faith in the writers that they would make these six seasons of mystery and confusion pay off big time.

Ah, but to paraphrase Widmore, “The island isn’t done with us yet.”

What did you think about last night’s episode? Do you think Desmond and Penny — and for that matter, the other castaways — will eventually find their happily ever after?